wdrag

Good morning again... I need a little help here from our XMACIS climate experts. Sooo many posts. I may have missed something you already did. The attached is CP max snowfall in an 8 day period in their entire climate history. Seems like we're heading into special territory if we get the ~6" forecast for tomorrow in CP. Already 15.4. Your thoughts? Thanks.

First cut on snowfall yesterday: CoCoRAHS

649A/8. Little change to the thread, except greater emphasis on snow event. Hazardous snowfall of 2-5" for the entire I84 corridor. Mostly the daylight hours but starts ne PA/nw NJ 3A-6A; CT-MA 7A-9A. Will melt on treated roads but caution advised hills and secondarys. Heaviest NORTH of I84, especially northern CT where ~4" common. Expect 1-3" here in northern NJ possibly down to Easton PA as well. Could be a little ice I80 southward too. Plan for possible travel slowdowns. NYC-LI--- looks like snow to start but melts during the late morning afternoon and may change to rain? My take is 1/2" NYC but uncertain. I just worry about melting-like yesterday when probably more fell than the 4.5 recorded but melted-compacted due to urban heat. WPC probs issued early this morning for 1 and 4". Use-rely upon as you prefer. It's going to snow, even NYC but how much NYC-LI and central NJ?? 716A/7 No change to this thread. Think this is reasonable. NYC might get a little wet snow accumulation from this but still on the margins. Will look at this much more closely Monday morning. Overall...a minor event except for where a few vehicles slide off the road along the I84 corridor or folks slip and fall stepping outside in that area, even down into the suburbs immediately west and north of NYC. Sometimes most of the accidents are in these small events. Therefore, even though a minor climo event for the wintry weather elements, it's still significant for those who are directly impacted. It appears LI (NYC) and the region along and s of I78 will be too warm for any accumulative snow, but it is not impossible to see several hours of wet snow there as well with something minor, especially if it arrives prior to 9AM. This primarily looks to be ne PA/nw NJ potentially hazardous snow event across to CT/MA. Amounts east of the CT River may end up closer to the 5" of the expected 1-5" range. This is a WAA pattern behind the departing Super Bowl Sunday event. Tentatively expect all treated valley and coastal roads will be mostly wet but could be slippery at times? Hilly terrain should be slippery at times, despite treatment. This water content, while minor, adds to the accumulations already on the ground and well insulated or unheated roofs PA/NJ/NYS/CT. Will add more graphics tomorrow, once we get past Super Sunday. The initial graphic is the low chance of 3"+ of snow per the WPC ensembles.

Will add a new thread for the 9th by 8A/6. Another event seems on its way (not necessarily the 14th), but more so the 16th-17th---that one might be sizable. I do think folks I95 northwest will need to monitor roof loads, gutter damming the next two weeks for safe .. SAFE mitigation processes. Not worth a concussion, broken leg or worse but it appears to me a fair amount of wintry qpf is coming the next 12 days. Everyone for fire hydrant clearance when possible, especially late 7th, late 9th, and 13th.

By the 13th I do... my guess is 3-6 for you Sunday, T-1" if snow Tuesday,, then next Thu possibly several inches, then ice Friday and end as snow early Sat. That latter uncertain on amounts of the ptypes. Definitely safe mitigation considerations... no science on my part but based on your report, melt damming in gutters and where SAFELY-SAFELY possible, ease snow loads on roofs. Definitely not worth a broken leg, concussion or worse. There's another behind this the 16th-17th ish I think. All of this is modeling based. '

8AM Thursday the 11th. One event closing out this morning and the the OBS thread will have a CoCoRAHS post around 11A, and a two day summary Saturday at 10AM. Whats coming? I dropped the wind event from the original post on the 5th and also the coldest of the season NYC. Nothing the 12th (my prior concern but unmodeled). 13th.. appears snow or sleet develops late Saturday, probably after dark and ends sometime Valentines Day. Details to be determined. Current modeled warming aloft near 850 MB suggests mostly sleet/freezing rain south of I84 with any snow snow accums in the bulk of the forum under 1" (if anything more than two tenths inch); with 1-4" snow accumulations reserved for the I84 corridor. This is modeled as generally light and appears to be an advisory event due to the probable ice mix southeast of I84. My concern is that modeling of the warming aloft in our subforum I78 northward may be too much, which would allow for a little more snow than now modeled. Jury out. I'm awaiting further model cycles. These impressions include seeing op cycles through 06z/11. -- 235PM Wednesday update (10th): Obs thread updated at 225PM with little change from my 7A Wednesday update; I still think be wary of the dry models for the 12th per the brief potential 6 hr sw 850MB flow WAA pulse (light snow PA/NJ). 13th...seems like steady snow develops for sure late on the 13th in our subforum,. Please see the 14th-18th thread on amounts for the 14th. 7A Wednesday update: The 11th is covered now in the OBS thread. The 12th...be wary of the dry models. Already WAA late 12th in PA. From the initial thread, I left the door open for the 13th. Given the early issuance of the thread on the 5th, I see this as the event occurrence but timing uncertain. Lots going on and timing of late 12-13 unknown, but just a piece of WAA snow. The idea of the coldest of the season NYC probably won't work out for the 13th-14th. Seems like this is mostly snow and won't quote a general amount by the end of the 13th yet. 538A Tuesday the 9th update: Modeling has trended south and remained south, so far, so that our subforum is on the northern fringes of events on the 11th and 12th, and have no idea of the 13th. Modeling is varied but overall depressed. Dropped the 1/2-1" qpf from the title and just riding out. Doesn't seem like much except s of I78 where a few inches of snow may occur, with an inch or so possible the rest of the subforum south of I84. Probably nil far northern CT. Still a delicate balance of short waves moving east-northeast in a fast flow with WAA just to our south. So not giving up completely but the heavier potential from the 00z/6-7 cycles has shifted south. 807A Monday the 8th: Thursday-Friday the 11th-12th: May drop the 13th from this thread tomorrow?? All else is okay, despite some of the more tempered modeling. Too much potential. Need to wait it out another day before any southward adjustments. Periods of snow especially PA/NJ with less certainty northern CT. My initial expectation from Baltimore northward is anywhere from 2-10" total by 11PM the 12th. Best chance of large accumulations I80 southward but who gets what?? Does look like travel problems at times, especially if the first part develops near midnight Thursday morning (or late Wednesday evening the 10th). Snow accums may only be 2" Philly to Baltimore because of freezing rain/sleet? That would place best axis of accumulative snow somewhere down across central NJ in the southern part of our NYC subforum. Lots of uncertainty on details. The 10" may be high but it was initial impression yesterday and I don't drop that unless it's clearly not happening. Ensembles suggest decent snowfall and modeling may yet trend back north? This should bring NYC 1-2" for starters. Think the NAM/RGEM will be helpful on trends. No GFSv16 available (to my knowledge). I do see the 06z EC op is pathetic here in our subforum the 11th. For now, awaiting clarity in modeling. I do like seeing the 06z/8 GEFS qpf and staying further north and snowy on the 11th. Periods of snow especially PA/NJ with less certainty northern CT. My initial expectation from Baltimore northward is anywhere from 2-10" total by 11PM the 12th. Best chance of large accumulations I80 southward but who gets what?? Does look like travel problems at times, especially if the first part develops near midnight Thursday morning (or late Wednesday evening the 10th). Snow accums may only be 2" Philly to Baltimore because of freezing rain/sleet? That would place best axis of accumulative snow somewhere down across central NJ. Lots of uncertainty on details. The 10" may be high but it was initial impression yesterday and I don't drop that unless it's clearly not happening. Ensembles suggest decent snowfall and modeling may yet trend back north? This should bring NYC 1-2" for starters. Think the NAM/RGEM will be helpful on trends. No GFSv16 available (to my knowledge). 730A Sunday: Why stop now... adding NWS ensemble statistical chance of 3" for the 11th-early 12th as more primer for what is coming, (two events or one continuously long 36+hour overrunning? My perspective only is a range of 1-12" for this event with base 1-2" everywhere in our NYC subforum before any change to ice/rain along and s of I80 by the 12th. Best potential for 12" north of I80 (not guaranteeing amounts this high but I think it's good to set a range of possibilities). In other words a decent winter storm is coming but phase changes and amounts of each are in model doubt. I do think ice will eventually occur all the way up to ~I84 with rain on LI and the NJ coast. 743A Saturday 2/6: Added the first graphic from WPC... the rather robust and large coverage Day 7 prob of 3+" of snow-sleet. Uncertainty exists a week in advance on the tracking/merging/intensity of surface lows passing northeastward through the northeast USA late next week. Initial indications are that the event should begin as snow (possibly significant) and may change to ice and rain for a time before ending with a wind driven shot of possibly our coldest air and wind chills by Saturday night the 13th. This event may end up coming in pieces...one on the 11th, with the main event seemingly dominating the 12th. If it is mostly snow, this would increase available potential snowmelt water for the spring.

Not starting a thread on the 9th (could be rain or a mix NYC) and its light, so that short duration accumulative snow event of 1-4" should be reserved for the I84 corridor. Feb 15-17...too far away with too much uncertainty but this too could be significant. Starting a thread for 11th-early early 13 in a few minutes. Thanks for all the comments-input-views.

Friday afternoon 509PM: Title change dropped late 6th-early 8th and reworded Description. NAM/GGEM/RGEM are tending to be the most robust of the models with a warnable 6-12" event LI and NJ basically s of I78 with lesser amounts north. Banding and decent snow growth may permit this but ensembles and other modeling indicate a little less. I think the minimum snowfall in our NYC subforum counties will be 2". Am not too worried about sleet on the southern edge for our area. Bottom line, shovels and snowblowers will be needed before the Super Bowl and safely keep those hydrant areas cleaned, and gutters from having dammed up meltwater icicles. Flat roofs might have some structure problems if the water content of the remaining snow exceeds limits (unknown to me). If removing snow, especially roofs/gutters-----safety FIRST.

Will catch up around 5P with probably 2 or 3 new threads dependent on ensembles for the period Feb 9-17. Hope no one gets sick and tired of snow/ice in our forum. Snowloads could be a problem by the 13th or 17th. Clear those hydrants for emergency access. Thread potential for a minor event Feb 9ish (WAA), a big storm Feb 12-13 and possibly another around the 16th-17th. Need some modeling to downplay one of the 3 and then will go from there. QPF between 7th-17th could exceed 2" and if mostly snow would be a problem atop what's already settled/melted and will refreeze. We seem to be in a highly anomalous period with an unusual sequence of rapidly following 6+ ince snow storms near the I95 corridor. I probably would not harken on general experience that it can't happen... Already possibly two 6+inch snowstorms within 7 days of each other NYC, and maybe another to follow within week (or maybe not?). I just want to digest all the ensembles and op modeling (CFS included).

Will recheck the topic headline at 4aP in light of 12Z/5 multiple models 5+ NYC and a moderate fast moving Nor'easter snowstorm for Sunday.

I saw the 12z/5 NAM. I sure hope RGEM/GGEM CATCH UP... nice storm, no matter whether warnable or just advisable. NAM is definitely on the higher side and consistently so. Will review details for myself at 330P and then check back.

Cant answer. I do think CoCORAHS is stable on DAILY snow depth...not necessarily total daily snowfall and so NWS 4 clearances/day or max SD is best in the 24 hour period.

Wantage NJ 0.6" 720A-950A. Season 45.8".

Wantage NJ 0.4" at 855A and snowing 3/4s- nice sized flakes at 909A. Almost over here. Will post final by 1015A.

15" if you report to the NWS. . CoCoRAHS is one ob only/day, but since you have two days and you state 12 on D1, and 3" new on D2, then thats 15, despite the lesser D2 SD(snow on the ground) of 13.5. Does that work? Walt

It's still here into at least 2022.

Am on the cusp of a Topic for a potentially large event Feb 12-13, snow ice and maybe even rain. Would like to see a little GEPS or EPS consensus. I'll add a few graphics from ensembles and hold off til either late today or tomorrow if the model vision continues. In essence a little WAA snow or ice on the 9th (no thread unless the snow-ice sags south to I80-LI), then turning a bit colder in advance of what appears to me to be a developing trough in the eastern USA around the 13th. There could be a lead short wave on the 12th that splits the energy. It might be better that way because if all the energy goes into one primary, that primary might go west of us. For now am going to count on overall blocking being an assist to the colder side. Really would like to see a bigger southward dive to the trough but what you see attached should be a good start. Have added the 00z/5 RMOP which is arguing for a trof - positive tilt for now Great Lakes southward and the comparison look from 00z/4 which had a flat w-e flow with a modest vortex over se Canada. Thats the change in 24 hours. Then the 06z/5 GEFS mean trough with the blocking in eastern Canada, followed by the 06z/5 GEFS Plumes for qpf at LGA. I didn't post snow plumes because their are precip type issues so resultant snow etc is up in the air, and finally the chance of 1"+"of qpf in 48 hours...already about 60% just on the southern edge of the forum. No guarantees that much qpf but I do think an event is coming, at least with a period of wintry precip types for part of the event.

Wantage NJ 0.3" in 40 minutes. treated roads wet. continues to snow. back down to 31.5 after briefly up to 33.

Wantage NJ, first batch prior to sunrise passed overhead with nary a flake, but SB 720A and about 0.2" in 20 minutes with temp having risen from the 20s early today to 33.1F now with main roads wet.

Friday the 5th - 649AM: Little change. Snow is coming and will continue increasing area seasonal snow totals higher (pushing normal or above by the start of the Super Bowl). I haven't checked seasonal normals except what I know for NYC (already above) and our area of nw NJ (at or above). Thinking the 06z/5 NAM may be a bit robust and since the GGEM/RGEM are keeping the bigger snowfall se NJ southward, therefore am reluctant thinking of warning amounts in our subforum, more generally a 1-5", 6-12 hour snowfall North to South. A pleasant refresher on an almost national holiday. Graphics are 1) NWS statistical ensemble chance of 2+" by the time the Super Bowl is complete (does not include this morning). 2) NWS snow forecast issued at 4am/5.

Good morning, the lead band already into western New England has been mostly aloft although it should be reaching the ground there very soon. Meanwhile, the main band in eastern PA at 630AM is producing snow. I see mPing even has flurries happening in the Hudson Valley. This probably won't be a big deal for most of us except for 2 hours in nw NJ/se NYS/ne PA where a quick 1/2-2" should occur with the heavest in the high terrain. The region NJ immediately west and southwest of NYC (I-I195 northward) sees a period of snow/sleet or even possibly freezing rain this morning where it all ends by 10 or 11am.

Hi! No topic quite yet for 9/10??, or more likely 12-14, but need another day or two to see if modeling is erratic. I like the potential. We're certainly on the northern side of an active blocked southern stream. It's how far north that they can poke northward?

I'll update in the morning if any change from this morning and the initial thread. I think the range in our forum is generally 1-9" with 9" unlikely (NAM already has 8" as did the EC wayyy back) but we want to resolve the model differences. For the heavier 4+ amounts I want to the see GGEM/RGEM continue to edge north in their future cycles and remaining models hold firm. Overall, I see a potential advisory event for a portion of the forum but cant rule out 6+ LI/NJ. Will take a longer look at this tomorrow. The only other note I have, if this does come to pass, as it appears, this will be the second successive event that the EC had a good idea about 5-7days out or beyond, and then all models lost it at about 96-114 hours and recovered northward (not as far north as D6-7) beginning at about 84 hours. Others might see it different? It remains to be seen if this forecast on forecast is going to verify. This history of models losing an event well modeled in the courser modeling 6-7 days in advance and then losing it closer in, hen reacquiring in the shorter term dates back decades. This is written (96-120 hr loss, then reacquisition ~84 hours) needs to be debunked, or, it's something that I will be looking forward to, the rest of this winter, for possible subsequent events. Later, Walt

A challenging period of travel is possible Friday morning across northwest NJ, northeast PA and se NYS; possibly into the CT portion of our forum as multiple bands of precip sweep eastward across the region. Amounts will be light but where possibly freezing rain or sleet, untreated surfaces could be quite slippery. Additionally there will be a tendency for any rain/freezing rain to briefly change to steady snow even to just west and north of NYC with little or no accumulation there, while high terrain in nw NJ/ne PA/se NYS and w CT are modeled to pick up 1/2-2" before melting begins ~ 11 AM or Noon. mPing. This thread will help concentrate interest Friday mornings system while the other threads occupy the Sunday event and beyond.

Ok... I have a SREF source and its waist a hit, but I do see the hit by the NAM. Haven't seen anything else for the 12z cycle and am off line til 530P. I think this is a very good sign and am counting on an event for Sunday. Hopefully RGEM supports as well as future 12z/4 GFSv16/GGEM.